1. Field of the Invention
The invention relates to a pixel structure and a fabrication method of the pixel structure. More particularly, the invention relates to both a pixel structure that has a high aperture ratio and can be easily fabricated and a fabrication method of the pixel structure.
2. Description of Related Art
In general, a pixel structure of a liquid crystal display (LCD) includes active devices and pixel electrodes. The active devices serve as switches of LCD display units. To control each pixel structure, a certain pixel is usually selected by a corresponding scan line and a corresponding data line, and display information corresponding to the pixel is displayed through providing an appropriate operating voltage. The pixel structure further includes storage capacitors, such that the pixel structure can be provided with a voltage-retaining function. Namely, the storage capacitors can store the applied operating voltages to stabilize the display image of the pixel structure.
To form the storage capacitors in the pixel structure, capacitor electrodes are often required in the pixel structure. However, in order to increase the capacitance of the storage capacitors, the area occupied by the capacitor electrodes need be expanded. In general, the capacitor electrodes are made of non-transparent conductive materials including metal, and the expansion of area of the capacitor electrodes results in the expansion of the non-transparent area; namely, the aperture ratio of the pixel structure is reduced. Besides, there is no other conductive element between the pixel electrodes and the data lines in the pixel structure, and thus the coupling effects between the pixel electrodes and the data lines pose an impact on the display quality of the pixel structure. Therefore, the pixel electrodes and the data lines must have a certain distance therebetween, which further limits the display aperture ratio. As a result, the existing pixel structures are not apt to be characterized by both the high image quality and the ideal display aperture ratio.